Computational modeling of localized corrosion in steel pipelines supported by composite sleeves

Pitting corrosion is a worrying phenomenon in the oil industry representing a major threat that can lead to the reduction of the structural integrity of pipeline transportation networks. To prevent this corrosion risk, active cathodic protection with a potential maintained at – 850 mV Cu/CuSO4 is used as a coating protection system based on bituminous binders to isolate the steel from the corrosive soil environment in hydrocarbon transportation pipelines. In this work, we examine the clock spring repair method by applying composite paths including a numerical simulation on corroded tubes using ANSYS software. The approach involves analyzing the structure under three scenarios: without defects, after the introduction of elliptical simulated corrosion pits, and following repair with multilayer reinforcement using a composite sleeve. The results indicate that the stress distribution varies across each scenario. In the case of a structure with parabolic corrosion defects, the Von Mises stresses are unevenly distributed. The defect exhibits a peak stress that could lead to the propagation of corrosion pits, necessitating repair. Conversely, in the scenario where the corroded structure is reinforced with a composite sleeve, the maximum Von Mises stress is decreased to levels comparable to those of an uncorroded pipe, demonstrating the necessity and effectiveness of using composite sleeve reinforcement

IN VITRO EFFECT OF ACETYLSALICYLIC ACID ON CALCIUM OXALATE CRYSTALLIZATION: AN APPROACH TO ANTILITHIASIS

Objective: In recent years, significant progress has been made in identifying and counting physico-chemical processes involved in urinary stone formation. The ability of urine to inhibit calcium oxalate crystallization is considered an important mechanism against stone formation. Several natural substances were tested to inhibit calcium oxalate crystallization. In the present study, we evaluate the effects of acetylsalicylic acid, also known as Aspirin, as an inhibitor of calcium oxalate crystallization in vitro.Methods: The nucleation and aggregation of calcium oxalate crystals were studied using turbidimetric 400-sec time course measurements of optic density at 620 nm after mixing solutions containing calcium chloride and sodium oxalate at room temperature, pH 5.7. The formation of crystals is induced by the addition of the oxalate to calcium solution. The effects on calcium oxalate crystal growth of acetylsalicylic acid with various concentrations were examined. The maximum increase of optic density in the course of time reflects maximum rate of formation of new particles. After reaching equilibrium, a progressive decrease of optic density with time is observed. Rate of aggregation is derived from the maximum decrease in optic density.Results: The results showed that if a concentration of acetylsalicylic acid is more than 1,66 mM both rate of formations of new particles and Rate of aggregation decreased (P<0.05).Conclusion: acetylsalicylic acid has a significant effect on nucleation as well as on crystal growth stage; consequently, it inhibits the crystal formation of calcium oxalate urinary lithiasis. Â

Printemps arabe : de l’événement à la formule discursive

L’expression «  printemps arabe  » désignant les mouvements qui éclatent en 2011 en Tunisie puis dans d’autres pays, va occuper, dès son apparition, une place considérable dans les discours politiques, médiatiques et publics. De son statut de mot événement, l’expression accède à une nouvelle fonction dans le discours : celle de formule. Inspirée des travaux de Krieg-Planque sur la formule en discours, la perspective proposée dans cet article est d’interroger la notion de «  printemps arabe  » et suivre son destin formulaire lié à l’ordre événementiel et à son interprétation à travers l’espace discursif auquel elle participe.The expression of "Arab Spring" designating the movements that broke out in 2011 in Tunisia and then in other Arab countries, has occupied a considerable place in political, media and public speeches. From its status as a neologism, the expression accesses a new function in the discourse : that of formula. Inspired by the works of Alice Krieg-Planque on formula in discourse analysis, the perspective proposed in this article is to question the notion of "Arab Spring" and follow the change in its discursive formula related to the event and its interpretation through the discursive space in which it participates

Optical and photovoltaic properties of indium selenide thin films prepared by van der Waals epitaxy

Indium selenide thin films have been grown on p-type gallium selenide single crystal substrates by van der Waals epitaxy. The use of two crucibles in the growth process has resulted in indium selenide films with physical properties closer to these of bulk indium selenide than those prepared by other techniques. The optical properties of the films have been studied by electroabsorption measurements. The band gap and its temperature dependence are very close to those of indium selenide single crystals. The width of the fundamental transition, even if larger than that of the pure single crystal material, decreases monotonously with temperature. Exciton peaks are not observed even at low temperature, which reveals that these layers still contain a large defect concentration. The current–voltage characteristic of indium selenide thin film devices was measured under simulated AM2 conditions. The solar conversion efficiency of these devices is lower than 0.6%. The high concentration of defects reduces the diffusion length of minority carriers down to values round to 0.2 μ[email protected] ; [email protected]

Sustainable water treatment: Harnessing mining waste as catalysts for Sicomet green degradation

This paper presents a novel circular economy approach to water remediation that focuses oncreating sustainable systems by utilizing mining waste from El-Ouenza, Tebessa, in the east ofAlgeria. Waste materials are employed as catalysts in Fenton and photo-Fenton processes. Twocases were studied: the conventional and the modified heterogeneous photo-Fenton at a pH of 3and under modified pH conditions for degrading Sicomet Green food dye ZS120. Catalysts werecharacterized through various analyses. Catalyst performance and dye degradation were examinedfor raw and calcined waste at 500 ◦C. Parameters like catalyst amount, sodium sulfiteconcentration, oxalic acid, and pH were optimized for both systems, with and without ligand. Thefirst system achieved 91.5 % mineralization using 0.15 g L\u100000 1 catalyst, pH of 3, and 0.45 mMNa2SO3 in 90 min under sunlight. The second reached 78.5 % efficiency with variable conditions.Kinetic models demonstrated a first-order model for both photo-Fenton degradation and mineralizationunder sunlight. These findings guide eco-friendly dye degradation via mining wastebasedcatalysts in photo-Fenton systems, supporting sustainable wastewater treatment

AML with inv(16)/t(16;16) and high-risk cytogenetic abnormalities: atypical features and unfavorable outcome

Objectives: Acute myeloid leukemia (AML) with inv(16)/t(16;16) is among the most frequent AML subtypes. It is recognized by the detection of the CBFB-MYH11 fusion which confers a favorable prognosis, irrespective of the presence of secondary cytogenetic abnormalities. However, the effect of additional genetic anomalies on the behavior of inv(16) AML is debatable. Recent case reports describe an unfavorable prognosis for those patients, characterized by early relapse and death. In this study, we present a series of patients with CBFB-MYH11 fusion and high-risk rearrangements to increase knowledge about this potentially distinct subgroup. Methods: All cases with inv(16)/ t(16;16) and one or more high risk abnormalities were reviewed at two tertiary healthcare centers between years 2006 and 2020 in terms of demographics, biological and clinical data. Results: Among the total 1447 and 1283 AML cases, the frequency was found to be 0,2% and 0.3%. Clinical data could be retrieved for 5 patients. Detected high-risk abnormalities included TP53 and 5q deletion, complex and monosomal karyotype. The median age was 67 years, with a majority of females (M:F = 1:1.5). Two out of 5 patients presented with therapy related AML, with short latency periods. All patients presented with thrombocytopenia and/or leukocytopenia. Bone marrow aspirates revealed atypical morphology and the detection of rare CBFB-MYH11 fusion transcripts. All 5 patients died, with a short mean overall survival of 5.8 months. Discussion and Conclusion: Our series suggests that the presence of high risk abnormalities confers distinct biological features and poor prognosis to inv(16) AML. © 2022 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group

The Case for Visual Analytics of Arsenic Concentrations in Foods

Arsenic is a naturally occurring toxic metal and its presence in food could be a potential risk to the health of both humans and animals. Prolonged ingestion of arsenic contaminated water may result in manifestations of toxicity in all systems of the body. Visual Analytics is a multidisciplinary field that is defined as the science of analytical reasoning facilitated by interactive visual interfaces. The concentrations of arsenic vary in foods making it impractical and impossible to provide regulatory limit for each food. This review article presents a case for the use of visual analytics approaches to provide comparative assessment of arsenic in various foods. The topics covered include (i) metabolism of arsenic in the human body; (ii) arsenic concentrations in various foods; (ii) factors affecting arsenic uptake in plants; (ii) introduction to visual analytics; and (iv) benefits of visual analytics for comparative assessment of arsenic concentration in foods. Visual analytics can provide an information superstructure of arsenic in various foods to permit insightful comparative risk assessment of the diverse and continually expanding data on arsenic in food groups in the context of country of study or origin, year of study, method of analysis and arsenic species